There are many situations where, after adjusting two contact surfaces in relation to each other, it is desirable to temporarily lock the surfaces in the adopted positions, without any possibility of them sliding. To adjust the position or to assume new relative positions between the contact surfaces, they must be able to be easily released from each other again.
There are innumerable examples of when a function as set out above is sought. One example is that of golf clubs, in the case of which the player, before taking a shot, wants to be able to adjust his grip round the club shaft to the exact position desired, and, when this position has been reached, to lock the club shaft securely between the hands in the adopted position. To solve this problem, it has previously been proposed to use different materials for the club handle which, together with a friction glove, is intended to give the best possible grip, see for example U.S. Pat. No. 3,649,967. However, no entirely satisfactory material combinations have as yet been developed which do not entail a risk of relative turning between the shaft and hands. In moist conditions or rain, the problems are aggravated because the friction between club shaft and glove is reduced.
Corresponding problems are also found in other sports where one has to be able to securely hold an item of sports equipment, for example various rackets, hockey and bandy clubs, baseball bats, bicycle and motorbike handles, steering wheels in cars, reins in equestrian sports, etc. The problems are at their worst in rainy weather and in extremely hot conditions as a consequence of sweat on the hands.
Similar requirements also exist in other areas, for example in tool work, for gripping a hammer, a screwdriver shaft, etc.